Inhibitor of fibrinolysis in human arterial wall

Abstract

Fibrinolytic system in the arterial wall seems to play an important role in the development and progression of atherosclerosis and in the formation and resolution of thrombi. Vascular plasminogen activator has been reported to be produced and secreted by endothelial cells, but fibrinolytic inhibitor in the arterial wall has not been fully investigated. Therefore we studied the inhibitor of fibrinolysis in human arterial wall.Results:1. Inhibitor of fibrinolysis was found in the intima and media of human arteries, and also in the atherosclerotic lesion.2. Acetone powder of the intima and media of human aorta was extracted with cold saline and partially purified by the procedures including ammonium sulfate fractionation, Concanavalin A-Sepharose affinity column, DEAE-Sepharose CL-6B column, and immunoadsorbent column chromatography.3. The final preparation was shown to be immunologically different from known serum protease inhibitors, and suggested to be a glycoprotein originated from tissue.4. The inhibitor suppressed the fibrinolysis induced by urokinase and partially purified tissue plasminogen activator, and hydrolytic activity of urokinase directly.This inhibitor may play a regulatory role on fibrinolysis in arterial wall and may play a role in the development and progression of atherosclerosis.